Automatic draft regulator for boilers



Dec. 11, 1928'.

L. W. EGGLES TON AUTOMATIC DRAFT REGULATOR FOR BOILERS Filed Nov. :50, 1925 2 Sheets-Sheet 1 ATTORNEY Dec. 11, 1928.

1,695,243 L. W. EGGLESTON AUTOMATIC DRAFT REGULATOR FOR BOILERS Filed Nov. 30, 1925 2 Sheets-Sheet 2 [11/ III/ll IIIJJIIIII MEI] HIP"

- INVENTOR 4, ATTORNEY Patented Dec. 11, 1928 UNITED STATES PATENT OFFlCE.

LEWIS W. EGGLESTON, OF BUFFALO, NEW YORK, ASSIGNOR T0 AMERICAfi RADIATOR COMPANY, OF CHICAGO, ILLINOIS, A CORPORATION OF NEW JERSEY.

AUTOMATIC DRAFT REGULATOR FOR BOILERS.

Application filed November 30, 1925.

My invention relates to improvements in heating apparatus, and the same has for its object more particularly to provide a sim ale, compact and ellicient device for controlling the rate of fuel consumption in a boiler, furnaoe or similar apparatus.

Further, said invention has for its object to provide a temperature regulating d vice which is controlled by means responsive to conditions within the heating apparatus.

Further, said invention has for its object a temperature regulating device which is ca pable of adjustment to predete mine the temperature at which the heating apparatus is to be maintained.

'Further, said invention has for its ect to provide an arrangement in which the position of the damper operating mechanism may be adjusted relative to the device responsive to conditions within the boiler to predetermine the temperature at which said mechanism is to be actuated by said device.

Further, said invention has for its object to provide a draft regulator in which the adj ustable means employed to predetermine the temperature at which the heating, apparatus is to be maintained will also serve to manually control the admission of air to said apparatus.

Other objects and advantages will in par be obvious and in pa t be pointed out hereinafter.

To the attainment of the aforesaid objects and ends my invention consists in the novel details of construction, and in the combination, connection and arrangement of parts hereinafter more fully described and then pointed out in the claims.

In the accompanying drawings forming part of this specification Figure 1 is a side view, partly broken away and sectioned, showing a boiler provided with a regulator embodying. the principles of my invention.

Fig. 9. is a central vertical side sectional view through the draft regulator.

Fig. 3 is a rear view of the regulator, and

Fig. 4 is an enlarged detail section on the line 44 of Fig. 2.

In said drawings there is shown a combined boiler and heater 10 comprising a hollow front section 11, a hollow back section 12, and a plurality of substantially loop-shaped in- Serial No. 72,083.

termediate sections 13. The front section 11 is provided with the usual fuel opening having a door 18", a slicing opening having a door 1%, an ash-"sit opening having a. door 15, and adjacent to its top with a flue opening provided with a door 16.

llithin the boiler, between the front and back sections 11 and 12, are arranged a plurality of great bars 17 positioned side by side and longitudinally of the boiler. At the upper rear end the boiler is provided with a smoke outlet 18. In the back section 12', adj a cent the bottom of the boiler, is provided a cold air inlet 19 which communicates with the interior of the boiler below the grate 17.

l Vithin the back section 12, near the upper end thereof, is formed a cavity 25 in which is positioned athermostatic device comprising an outer casing 26 and an inner metallic bellows 27, the space between the casing 26 and bellows 27 being filled with an operating fluid, such, for example, as kerosene, alcohol, ether or any other suitable volatile or expansible fluid. The outer end of said bellows is joined to the casing 26 to seal the space between them. At its inner end the bellows abuts against the casing 26 and is provided with a head 29 having a tube extending outwardly therefrom for charging the device. tubular plui'iger 31 surrounding the tube 30 as at its inner end the head 29 and .s outwardly and through a bracket 32 lined to the rear of the boiler, said bracket providing a bearing in which said tubular plunger works. The outer end of said plunger 31 provided with a yield-able head retained in position within the plunger 31 by means of the cap at threaded upon the outer end of the plunger, and through which said head 83 projects. A coil spring 35 is in terposed between the head 33 and an abutment 36 disposed within the tubular plunger 81.

A lever 3'? is pivotally suspended at its upper end, as more fully described hereinafter, and is provided with a bearing portion 38 engaging the head 33. At itslower end the lever 37 carries a damper plate 39 cooperating with the air inlet 19, and normally held in open position by suitable biasing means, such as the spring 40.

As long the the plunger 31 is in its retracted position, the lever 37 will maintain the air inlet open and permit of the increased supply of air which results in an increase of temperature. When the temperature rises sufficiently to contract the bellows, the member 33 and the upper end of the lever 37 move outwardly while the lower end of the lever moves inwardly to cause the plate 39 to seal the air inlet opening 19 until the rate of combustion is reduced. The long arm of the lever 37 greatly magnifies the movement of the damper plate 39.

In order to control the damper plate so that it will open and close at any desired pred termined temperature, there is provided, upon a spindle ll fixed to the bracket 32, a rotatable member 12 having a spiral groove 43 therein. A handle at is secured to the outer end of the rotatable member for actuating the same. An annular member or collar 4L5 works upon the rotatable member, and is provided with a suitable projection such as the screw 41-6, operating in the groove 43 to cause said member 35 to travel along the shaft 42 upon the rotation thereof. The lever 37 below the bearing surface 38 thereof is pivoted at 47 between the lower arms 48 of a vertically disposed bifurcated member 49 which has upper arms 50 disposed at opposite sides of the collar 45 and pivoted at 51 thereto. The member 49 intermediate its encs is also pivoted at 52 between the opposing portions of a horizontally extending member 53 pivoted at its inner end 54 to the bracket 32.

The upper end of the spring 40 is attached to the outer end of said member 53, and the lower end to said lever 37 intermediate the ends of said lever 37. The damper operating mechanism is enclosed by a suitable casing 55 having an opening 56 therein through which the shaft i3 projects, and having openings 57 in the lower portion thereof for the admission of air, the portion 58 of said casing serving as a stop to limit the outward movement of the lower end of the lever 37. The upper portion of the casing 55 has formed thereon suitable indications or calibrations 59 for assisting the operator in adjusting to the desired temperature, the handle 44 in front of the casing being provided with a pointer 60 cooperating with said calibrations, and also constituting a stop engage able with a cooperating stop 61 to limit the rotation of the member 42 in each direction.

In operation, by rotating the member i2, the position of the bearing member or portion 38 of the lever 37 is varied relative to the head 33 of the responsive device. With the apparatus in the position illustrated the collar 4-5 is at its outermost limit of travel. When in this position the member 49 has moved the upper end of the lever 37 inwardly. This inward movement causes the bearing portion 33 to press against the head 33, whereby the lower end of the lever is swung about the pivot 47 into open position. Thus, by

this arrangement means is provided for manually controlling the admission of air through the inlet 19. As the handle is rotated counter-clockwise, looking at Fig. 3, the bearing portion 38 is moved outwardly rela tive to the plunger head 33, the spring 4:0 maintaining the lower end of the lever in open position. By thus adjusting the relative positions of the bearing portion 38 and the head 33, the temperature at which the responsive device operates to actuate the lever 37 is also controlled. As the member 42 rotated counter-clockwise from the position illus trated proportionally higher temperatures must be attained before the lever is actuated by the head 33 to close the damper. ll hen the temperature is correspondingly reduced the spring 40 will move the damper plate away from the inlet 19.

The member 53 provides a yieldable fulcrum to permit of the movement of the link or actuating member l?) without causing binding of theparts, and the connection of the spring 40 thereto is such that the relative position of the upper end of the lever 37 may be adjusted without appreciably varying the tension of said spring, the temperature at which the lever is actuated depending upon the position of the upper end of the lever, and not being controlled by variation of the tension otsaid spring.

The spring 35 serves to normally maintain the head 33 in its outer position, and permits of the yielding of said head when an unusual or undesirably large force is applied thereto which might otherwise rupture or damage the collapsible element or bellows.

The lever 37 is freely suspended, and is extremely sensitive to variations of the responsive device, and adjustment to predetermine the temperature at which the regulator operates is made by varying the relative positions of the head 33 and upper cut 38 of the lever 37, the same adjusting means also serving to manually control the admission of air through said inlet 19.

While the above description contemplates control of: the draft in accordance with the temperature developed within the boiler, it will be apparent that said control may be made dependent upon the pressure in the boiler by merely removing the casing 26 and exposing the bellows 27 directly to said pres sure.

It is to be noted that all the openings in the front of the heating apparatus are closed by doors which are preferably ground to fit tightly against or over said openings in order to prevent any admission of air to the interior of the apparatus, and that the primary air necessary to support combustion is admitted to the heating apparatus wholly through the air inlet 19, which is automatically controlled.

The above description illustrates the prin llill ill) ciples embodied in my invention, but it will be understood that various changes and modifications may be made within the scope of the invention as defined by the annexed claims.

Having this described my said invention, what I claim and desire to secure by Letters Patent is:

1. The combination of a boiler having a main air supply inlet, with a support, a member movably mounted on said support, a lever pivotally suspended at its upper end from said member, a closure for said inlet connected to the free end of said lever, means responsive to conditions within the boiler and associated with said lever at the pivoted end thereof for actuating said closure to control the passage of air through said inlet; said lever tending to maintain said closure in open position, and means connected to said movable member for reciprocating the same to vary the position of said lever relative to said responsive means for controlling the operation of said lever, substantially as specified.

2. The combination of a boiler having a main air supply inlet, with a support, a member movably mounted on said support, a lever pivotally suspended at its upper end from said member, a closure for said inlet connected to the free end of said lever, means responsive to conditions within the boiler and having a plunger engaging said lever above the pivot thereof; said responsive means serving to actuate said lever to control said closure, and means connected to said movable member for adjusting the same towards and away from said plunger to permit of the manual control of said closure; said lastnamed means servingto control the temperature at which said closure is actuated by said responsive means, substantially as specified.

3. The combination of a boiler having a main air supply inlet, with a closure for said inlet, a lever to which said closure is attached at one end, means responsive to conditions within the boiler and associated with the other end of said lever for actuating the same, a support, a rotatable actuating screw thereon, and a pivoted member traveling on said screw and connected to said lever for varying the position of said lever relative to said responsive means whereby to control the temperature at which said closure is actuated by said responsive means, substantially as specilied.

l. The combination of a boiler having a main air supply inlet, with a reciprocating member, a pivoted supporting arm connected to said reciprocating member, a lever pivotally suspended at its upper end from said arm, a closure for said inlet connected to the free end of said lever, means responsive to conditions within the boiler and associated with the upper end of said lever for actuating the same, and means for actuating said reciprocating member whereby to adjust the position of said lever relative to said responsive means, and control the temperature at which said closure is actuated by said responsive means, substantially as specified,

5. The combination of a boiler havinga main air supply inlet, with a support, a rotatable actuating member thereon, a member adapted to travel on said actuating member when the same is rotated, a horizontally extending member pivoted at its inner end and disposed below said actuating member, a vertically arranged arm pivoted intermediate its ends to said horizontally extending member and at its upper end to said traveling member, a lever pivotally suspended at its upper end from the lower end of said arm, a closure connected to the lower end of said lever, and means responsive to conditions within the boiler and having a plunger engaging said lever above the pivot thereof, substantially as specified.

G. The combination of a boiler having a main air supply inlet, with means responsive to conditions within the boiler and having a plunger projecting therefrom, a support above the same, a rotatable screw upon said support, a collar adapted to travel upon said rotatable screw, a pivoted member disposed between said rotatable screw and said responsive means, a vertically extending arm pivoted intermediate its ends to said pivoted member and at its upper end to said collar, a lever pivotally suspended at its upper end from said arm and having a portion above its pivot engaging said plunger, a closure for said inlet connected to said lever at its lower end and controlled by the operation of said responsive means, and a spring connected at one end to said pivoted member and at its opposite end to said lever; said rotatable screw serving to adjust the position of the pivot of said lever relative to said plunger to permit of the manual control of said closure and to control the temperature at which said closure is actuated by said responsive means, substantially as specified.

7. The combination of a boiler having a main air supply inlet, with a reciprocating member, a supporting arm pivoted interme diate its ends and at its upper end to said reciprocating member, a lever pivotally suspended at its upper end from the lower end of said arm, a closure for said inlet connected to the free end of said lever, means responsive to conditions within the boiler and associated with said lever for actuating the same, and means for actuatin said reciprocating member, substantially as specified.

8. The combination of a boiler having a main air supply inlet and a support, with a rotatable actuating member thereon, a member adapted to travel on said actuating member=when-the same is rotated, a vertically-arboiler andassociated with said lever for acturanged arm :pivoted intermediate its ends ating the same, substantially as specified.

and nt-its upper end co-saidtravelingrnem- Signed-at the city of New York, in the 10 her, a leverLp'ivotaIly suspended at its upper county-and State of New York, this 28 day endifrom the lower 'end of said arm, a closure of November, one thousand nine hundred and connected tothe lower end of said lever, and twenty-five.

means responsive to conditions within the LEWVIS WV. EGGLESTON. 

